Viber app (iphone/android)

So i was wondering guys cause google gets me weird results does anyone know how this application store our data online (encrypted or not) and if there have been any known hacker attacks that resulted in information loss?
I am going to start using it so i wanted to ask a few opinion from fellow wbb members.
Thanks for your time and help.
Answer #1
Whatsapp?
Well I’m using it for a year or so…. and everything is ok…
Storing data? Like what?
Your mobile number?! That is nothing!
Answer #2
Yeah i was wondering about my number but ok not so important i guess. I am gonna check whatsapp plus i think i saw it before. Will google the app a bit and check.
Thanks.